Millions of epidural and peripheral nerve block anesthesia catheters are placed in the United States each year for indications including labor analgesia, open abdominal, thoracic, vascular, and orthopedic surgery, chronic and acute pain control, and many others. Epidural and peripheral nerve block anesthesia catheters are often utilized up to 7-10 days to provide pain relief in a post-operative patient. Unfortunately, the failure rate of epidural analgesia is reported to be as high as 30%.
Epidural and peripheral nerve block anesthesia catheters are fraught with a high rate of inadvertent dislodgement. Thus, one of the most common causes of epidural and peripheral nerve block catheter failure is catheter dislodgment, comprising 45% of all failures in one study, and 57% of all catheter related complications in another study. The overall rate of accidental catheter dislodgement depends on duration, depth of insertion, and external fixation technique, varying widely from as low as 3% to as high as 53% in some studies. Catheter dislodgement may effectively expose the patient to the risks introduced in epidural or peripheral nerve block placement while truncating the benefit, and potentially increasing the risk of epidural hematoma formation.
Several external catheter fixation techniques have been used in an effort to prevent catheter dislodgement and/or catheter migration. These techniques have included subcutaneous tunneling, suturing, and external fixation devices. However, none of these external fixation techniques have been widely adopted due to poor efficacy, concerns over infectious risk, and patient comfort.
Each time an epidural or peripheral catheter is inadvertently dislodged, man-power and materials are wasted in order to replace it. The patient often experiences worsened pain, which often is treated with systemic opiates, that have been shown to delay return of bowel function and lengthen hospital stay. In addition, patient satisfaction, an outcome measure which may likely become tied to reimbursement in the future, can decline when pain is inadequately controlled. Moreover, an inadvertently dislodged catheter in a coagulopathic or deliberately anti-coagulated patient can cause epidural hematoma formation, which is a complication that can be costly to treat.
Another key patient population where catheter dislodgement can carry significant hidden costs, both to the patient and facility, is the thoracic surgery patient. Thoracic surgery patients are often pulmonary cripples who are reliant on epidural analgesia to be able to take adequate tidal volumes with each breath. Loss of epidural analgesia in such patients can cause inability to wean ventilator support, or trigger the need for re-intubation, with all of the associated subsequent complications.
Lastly, long-term epidural catheters, such as those used for chronic pain in cancer patients, often have a higher rate of dislodgement. At the same time, this patient population would arguably have the highest costs associated with catheter dislodgment, as they are typically located away from the hospital, are difficult to transport, and have the most severe forms of pain.
Therefore, a catheter for accessing an internal body region (i.e., an epidural space, nerve region, or the like) is needed that overcomes the above limitations.